Device for reducing piston slap in internal combustion engines



March 1, 1932.

D. M. SOLENBERGER DEVICE FOR REDUCING PISTON SLAP IN INTERNAL COMBUSTION ENGINES Filed Sept. 24, 1928 ran tar Patented Mar. 1, 1932 UNITED STATESPATEN'IT OFFICE DEAN M. SOLENIBERGER, OF CLEVELAND, OHIO, ASSIGNOR TO THE SIMPLEX PISTON RING COMPANY OF AMERICA, INC., A CORPORATION OF OHIO DEVICE non. REDUCING rrsron s Ar m INTERNAL comans'rron enemas Application filed September 24, 1928. Serial No. 807,978.

This invention relates to devices for reducing slap of pistons which loosely fit their cylinders and of that type in which one side of the piston is held in contact with one side wall of the cylinder. Heretofore, devices of this character have'been 'made in which the piston is held in eccentric relation tothe cylinder through the medium of a piston ring, together with means for exerting resilient, pressure between the ring and the piston with a preponderance of said pressure 1n one direction. The means employed for exerting this resilient pressure is preferably a corrugated ribbon expander which lies between the inner surface of the ring and the bottom of the ring groove. The preponderance of pressure in one direction may be produced either by the use of an eccentric ring, that is, a ring that is thicker on one side than the other, or by an expander which on one side thereof is more rigid than upon the opposite side so as to exert'a higher pressure.

" Inasmuch as the greater tendency toward ponderance of pressure will be altered. It

F as

is the object of the present invention to prevent any shifting of the direction in which the preponderance of pressure is exerted, which I have accomplished by the-construe tion as hereinafter set forth.

lncthe drawings: Figure 1 is a central longitudinal section throu h an engine, cylinder and piston to D is a ring locate which my improvement is applied.

Figure 2 is a sectional plan view thereofl Figure 3 is a view similar to Figure 2 showlnga modified construction.

A designates a piston which is provided with a ring groovh B which is preferably arranged adjacent to the lane of the wrist pin (Fin the groove and E is a corrugated ribbon expander which is placed in the groove between the ring and'the bottom of the groove to exert a radially outward pressure on said ring. The preponderance of pressure in one direction may be produced in various ways, as for instance as shown in Figure 2 where the ring D is shown as eccentric or radially thicker on one side D than on the diametrically opposite side D?. This will causea greater compression of the corrugated expander E on the thick side of the ring with the result that the piston will be forced over to the diametrically opposite side of the cylinder and yieldably held in contact therewith. In the\ construction shown in Figure 3 the preponderanceofpiessureisproduced by a corrugated ribbon expander having the portion E on one side of greater thickness than the portion E on the diametrically opposite side. Thus the thick side of the expander is much more rigid than the thin side and will exert a correspondingly greater pressure against the ring.

With the construction as thus far described, the direction in which the preponderance of pressureis to be exerted is determined by the position of the ring on its expander in the ring groove, but there is danger that during the operation of the engine this direction may a be changed by the rotation of the ring or expander in the groove. Such a result I have prevented through the use of means for anchoring either the ring or its expander against any relative rotary movement with respect to the piston. Preferably this is accomplished through the attachment of a pin F to the ex ander or to the ring and engaging the pro ecti'ng end of this pin with a recess G in the piston shown in Figure 3.

'Whei'e, however, an eccentric ring is used as shown in Figure" 2, the pin F is preferably provided with an oppositely projecting por- 0 tion F 2 for engaging a recess in the ring D thereby holding both the expander and the ring from rotation.

It is obvious that in place of the pin F shown any projection from the ring or expander which has an anchoring engagement with the piston will answer the same purpose. Also in place of the specific means shown in Figures 2 and 3 for causing the preponderance of pressure in one direction any other suitable means for producingsuch a result ma be used.

o eration the ring D being split is free to rea ily expand under the pressure of the ribbon expander so that all portions of the periphery of the ring will force in contact with the walls of the cylinder. The preponderance of pressure is, however, in the di-' rection of the axis of the wrist pin and the anchoring meansshown prevents any shifting of the direction of such ressure.

However, as clearly shown in thedrawings, the pin F does not closely fit the recess G but has a slight clearance or a lost motion therein. This permits the breathing movement of the expander which is necessary when the piston moves up and down a tapered c linder and thus prevents overstressing and breaking of the expander at the pin.

What I claim as my invention is:

1. A device for preventing piston slap in loosely fitting cylinders comprising in combination with the piston having a ring groove, of a ring engaging said groove, a corru ated ribbon expander between said rin an the bottom of the groove, means by whlch a preponderance of radial pressure is exerted by said expander in one direction, and means loosely engaging said piston and said ring and expander at one end thereof for holding the same from circumferential displacement.

2. A device for preventing piston slap in loosely fitting cylinders comprising in combination with the piston having a ring groove, of a ring engagin said groove, a corrugated r1bbon expander etween said rin and the bottom of the groove, means by whlc'h' a preponderance of radial pressure is exerted by sa1d expander in one direction, and means loosely engaging said piston and connected to said expander at one end thereof for holding the same from circumferential displacement.

3, A device for preventing piston slap in loosely fitting cylinders comprising in combmatron with apiston having a ring groove, of a rmg'engaging said groove, a corrugated r1bbon expander etween said ring and the bottom of the groove, said expander being of greater thickness in one portion than in another to exert a proponderance of radial pressure in one direction and means loosely engaging said piston and connected to one en 0f Sa1d expander for holding the same from circumferential displacement.

In testlmon whereof I afiix my signature.

. D AN M. SOLENBERGER. 

